DH485 communication problem

[Ken Roach]

okay... fabricated by me, anyway (!)

The connector A-B uses for DH+, RS-232 on MicroLogix, and SCANPort plugs is called an "8-pin Mini-DIN". It's different from PS-2.

The 8-pin Mini-DIN connector on the MicroLogix is in fact unique; the locking collar is inverted from the "standard" Mini-DIN.

There's a very good reason for this; Pin 1 on the MicroLogix connector is +24 VDC, to power handheld programmers and network interface boxes like the Net-DNI and Net-ENI.

When I make my own connectors, I buy AppleTalk connectors at the surplus store for a couple of bucks, ring out the plugs carefully, then wire them up.

If you want a good latching connector, though, you pretty much have to buy an A-B cable and cut one end off.

 

[Tom Jenkins]

I've pretty much given up on building my own cable for A-B connections, especially to the non-standard mini-DIN plugs on the MicroLogix and AIC+ units. By the time you get done determining pin outs, finding parts, soldering, testing, cussing, etc. it is cheaper to buy the AB cables and be done with it. If you down load the AIC+ user manual from the AB site (Publication 1747-UM011C-EN-P) you find a pretty comprehensive cable part number guide in section 2.